package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    // 路径匹配器, 支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        long id = Thread.currentThread().getId();
        log.info("线程id: {}", id);

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        // 1. 获取本次请求的url
        String requestURI = request.getRequestURI();
        log.info("拦截到请求: {}",requestURI);

        // 定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg", // 移动端发送短信
                "/user/login" // 移动端登录
        };

        // 2. 判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        // 3. 判断登录状态, 如果已登录, 直接放行
        if(check){
            log.info("本次请求{}不需要处理", requestURI);
            filterChain.doFilter(request, response);
            return;
        }

        // 4-1. 判断登录状态, 如果已登录, 则直接放行
        if(request.getSession().getAttribute("employee") != null){

            Long empId = (Long) request.getSession().getAttribute("employee");

            BaseContext.setCurrentId(empId);

            log.info("用户已登录, 用户id为: {}", empId);
            filterChain.doFilter(request, response);
            return;
        }
        // 4-2. 判断登录状态, 如果已登录, 则直接放行
        if(request.getSession().getAttribute("user") != null){

            Long userId = (Long) request.getSession().getAttribute("user");

            BaseContext.setCurrentId(userId);

            log.info("用户已登录, 用户id为: {}", userId);
            filterChain.doFilter(request, response);
            return;
        }

        log.info("用户未登录");
        // 5. 如果未登录则返回未登录结果, 通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    /**
     * 路径匹配, 检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI)
    {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }


}
